Method for operating a computed tomography facility and computed tomography facility

Abstract

A method for operating a computed tomography facility includes, during an imaging process, dividing detector data into: (1) a first data stream with first detector data sufficient for the reconstruction of an evaluable computed tomography image dataset after completion of the raw data acquisition with the at least one X-ray detector with a data transmission rate corresponding at most to the maximum transmission rate; and (2) a second data stream comprising the remaining detector data as second detector data. The method further includes: transferring the first data stream as a real-time transmission directly to a computing facility via a communication path; storing the second detector data in a temporary storage facility; and, after completion of the raw data acquisition with the at least one X-ray detector and the transmission of the first data stream, transmitting the second detector data to the computing facility via the communication path.

1 . A method for operating a computed tomography facility having a rotatable portion with at least one X-ray detector and a portion fixed relative to the rotatable portion with a computing facility configured to process detector data recorded with the at least one X-ray detector, wherein the at least one X-ray detector is assigned a preparation facility for ascertaining detector data to be transmitted to the computing facility via a communication path from raw data of the at least one X-ray detector and the communication path has a wireless communication link with a maximum transmission rate, and wherein, during an imaging process, the method comprises:
 dividing, by a selection unit of the preparation facility, the detector data into: (1) a first data stream with first detector data that is sufficient for reconstruction of an evaluable computed tomography image dataset after completion of raw data acquisition with the at least one X-ray detector with a data transmission rate corresponding at most to the maximum transmission rate; and (2) a second data stream comprising remaining detector data as second detector data;   transferring the first data stream as a real-time transmission directly to the computing facility via the communication path;   storing the second detector data temporarily in a temporary storage facility; and   transmitting the second detector data to the computing facility via the communication path after completion of the raw data acquisition with the at least one X-ray detector and the transferring of the first data stream.   
     
     
         2 . The method of  claim 1 , wherein the first data stream comprises the first detector data that is at least partially reduced in spatial resolution and/or spatial coverage compared to all of the detector data. 
     
     
         3 . The method of  claim 2 , wherein a prespecified overall spatial coverage of the detector data is split into at least two subgroups, and
 wherein the raw data acquisition takes place in time steps and in each case only detector data of one subgroup of the at least two subgroups is selected into the first data stream in successive time steps according to a prespecified sequence of the at least two subgroups.   
     
     
         4 . The method of  claim 1 , wherein a temporal resolution of the first detector data is lower than a temporal resolution of all of the detector data. 
     
     
         5 . The method of  claim 1 , wherein the preparation facility comprises a transformation unit configured to ascertain a spatial frequency representation of the detector data, and
 wherein only detector data with spatial frequencies that satisfy a spatial frequency criterion is sorted into the first data stream.   
     
     
         6 . The method of  claim 1 , wherein, when detector data is omitted spatially, temporally, frequency-based, or a combination thereof for the first data stream, on the reconstruction of a computed tomography image dataset from the detector data of the first data stream alone, at least a part of the omitted detector data is reconstructed by interpolation and/or extrapolation. 
     
     
         7 . The method of  claim 1 , wherein the computed tomography facility is configured for spectral imaging,
 wherein the detector data comprises partial data assigned to different energy parameter values, and   wherein the first data stream only contains partial data for some less than all of the energy parameter values.   
     
     
         8 . The method of  claim 1 , wherein the division is carried out in order to make a greatest possible use of the maximum transmission rate. 
     
     
         9 . The method of  claim 1 , wherein the selection unit carries out the division according to at least one selection parameter prespecified by a control facility of the computed tomography facility. 
     
     
         10 . The method of  claim 9 , wherein the at least one corresponding selection parameter is assigned to each selectable recording protocol specifying acquisition parameters for the raw data acquisition and/or preparation parameters for the preparation and transferred to the preparation facility and set at the preparation facility before a start of the raw data acquisition. 
     
     
         11 . The method of  claim 9 , wherein the at least one selection parameter and/or selection information describing the division into the data streams is also transferred to the computing facility when, in an initialization act, the received detector data of the first data stream and the second data stream is combined to form a detector dataset suitable as input data for subsequent data processing operations of the computing facility. 
     
     
         12 . The method of  claim 1 , wherein, for transmissions via the communication path, a buffer memory is used that allows a data packet to be resent in an event of a faulty transmission, and
 wherein the buffer memory is implemented as part of the temporary storage facility reserved for this purpose.   
     
     
         13 . The method of  claim 1 , wherein, during the transmission of the second detector data, initialization information for the next imaging process is already transferred to the rotating portion. 
     
     
         14 . The method of  claim 1 , wherein, in an event of only partial transmission of the second detector data, which comprises additional information compared to the first detector data, due to an error, the computing facility is configured to add the additional information in the computed tomography image dataset at least with respect to a transmitted part. 
     
     
         15 . The method of  claim 14 , wherein the error is a system failure. 
     
     
         16 . A computed tomography facility comprising:
 a computing facility;   at least one X-ray detector;   a communication path having a wireless communication link with a maximum transmission rate;   a preparation facility configured to ascertain detector data to be transmitted to the computing facility via the communication path from raw data of the at least one X-ray detector; and   a rotatable portion with the at least one X-ray detector and a portion that is fixed relative to the rotatable portion with the computing facility configured to process detector data recorded with the at least one X-ray detector, wherein the at least one X-ray detector is assigned the preparation facility,   wherein the preparation facility comprises:
 a selection unit configured to divide the detector data of an imaging process into: (1) a first data stream with first detector data that is sufficient for reconstruction of an evaluable computed tomography image dataset after completion of a raw data acquisition with the at least one X-ray detector with a data transmission rate corresponding at most to the maximum transmission rate; and (2) a second data stream comprising remaining detector data as second detector data; 
 a temporary storage unit configured to temporarily store the second detector data of the second data stream in a temporary storage facility; and 
 a transmission unit for direct real-time transmission of the first data stream via the communication path to the computing facility and, after completion of the raw data acquisition of the imaging process, for transmission of the second detector data via the communication path to the computing facility.